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1.
Life (Basel) ; 14(2)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38398708

RESUMO

Hypertrophic cardiomyopathy (HCM) is a common genetic disorder with a well described risk of sudden cardiac death; however, risk stratification has remained a challenge. Recently, novel parameters in cardiac magnetic resonance imaging (CMR) have shown promise in helping to improve upon current risk stratification paradigms. In this manuscript, we have reviewed novel CMR risk markers and their utility in HCM. The results of the review showed that T1, extracellular volume, CMR feature tracking, and other miscellaneous novel CMR variables have the potential to improve sudden death risk stratification and may have additional roles in diagnosis and prognosis. The strengths and weaknesses of these imaging techniques, and their potential utility and implementation in HCM risk stratification are discussed.

2.
Sci Rep ; 12(1): 13163, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35915147

RESUMO

Biofilms, are significant component that contributes to the development of chronic infections, especially when medical devices are involved. This issue offers a huge challenge for the medical community since standard antibiotics are only capable of eradicating biofilms to a very limited degree. The prevention of biofilm formation have led to the development of a variety of coating methods and new materials. These methods are intended to coat surfaces in such a way as to inhibit the formation of biofilm. Metallic glassy alloys, in particular, alloys that include copper and titanium metals have gained popularity as desirable antibacterial coating. Meanwhile, there has been a rise in the use of the cold spray coating technique due to the fact that it is a proper approach for processing temperature-sensitive materials. The present study was carried out in part with the intention of developing a new antibiofilm metallic glassy consisting of ternary Cu-Zr-Ni using mechanical alloying technique. The spherical powders that comprised the end-product were utilized as feedstock materials for cold spray coatings to stainless steel surfaces at low temperature. When compared to stainless steel, substrates coated with metallic glassy were able to significantly reduce the formation of biofilm by at least one log.


Assuntos
Nanopartículas , Aço Inoxidável , Ligas/química , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes , Materiais Revestidos Biocompatíveis/química , Pós , Aço Inoxidável/química , Titânio/química
3.
Nanomaterials (Basel) ; 12(10)2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35630903

RESUMO

Antibacterial agents derived from conventional organic compounds have traditionally been employed as a biofilm protective coating for many years. These agents, on the other hand, often include toxic components that are potentially hazardous to humans. Multiple approaches have been investigated over the last two decades, including the use of various metallic and oxide materials, in order to produce a diverse variety of usable coating layers. When it comes to material coating approaches, the cold spray technique, which is a solid-state method that works well with nanopowders, has shown superior performance. Its capacity to produce unique material coating in ways that are not possible with other thermal methods is the primary reason for its importance in contemporary production. The present work has been addressed in part to explore the possibility of employing mechanically alloyed Cu50(Ti50-xNix)x; x = 10, 20, 30, and 40 at.% metallic glass powders, for producing an antibiofilm/SUS304 surface protective coating, using the cold spray approach. In this study, elemental Cu, Ti, and Ni powders were low-energy ball milled for 100 h to fabricate metallic glassy powders with different Ni contents. The as-prepared metallic glassy powders were utilized to coat SUS304 sheets, using the cold spraying process. With high nanohardness values, the as-fabricated coating material, in particular Cu50Ti20Ni30, demonstrated remarkable performance in comparison to other materials in its class. Furthermore, it displayed excellent wear resistance while maintaining a low coefficient of friction, with values ranging from 0.32 to 0.45 in the tested range. E. coli biofilms were formed on 20 mm2 SUS304 sheet coated coupons, which had been injected with 1.5 108 CFU mL-1 of the bacterium. With the use of nanocrystalline Cu-based powders, it is feasible to achieve considerable biofilm inhibition, which is a practical strategy for accomplishing the suppression of biofilm formation.

4.
Ecotoxicol Environ Saf ; 141: 298-305, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28365455

RESUMO

Large amounts of plastic end up in the oceans every year where they fragment into microplastics over time. During this process, microplastics and their associated plasticizers become available for ingestion by different organisms. This study assessed the effects of microplastics (Polyethylene terephthalate; PET) and one plasticizer (Di(2-ethylhexyl)phthalate; DEHP) on mortality, productivity, population sizes and gene expression of the calanoid copepod Parvocalanus crassirostris. Copepods were exposed to DEHP for 48h to assess toxicity. Adults were very healthy following chemical exposure (up to 5120µg L-1), whereas nauplii were severely affected at very low concentrations (48h LC50value of 1.04 ng L-1). Adults exposed to sub-lethal concentrations of DEHP (0.1-0.3µg L-1) or microplastics (10,000-80,000 particles mL-1) exhibited substantial reductions in egg production. Populations were exposed to either microplastics or DEHP for 6 days with 18 days of recovery or for 24 days. Populations exposed to microplastics for 24 days significantly depleted in population size (60±4.1%, p<0.001) relative to controls, whilst populations exposed for only 6 days (with 18 days of recovery) experienced less severe depletions (75±6.0% of control, p<0.05). Populations exposed to DEHP, however, exhibited no recovery and both treatments (6 and 24 days) yielded the same average population size at the termination of the experiment (59±4.9% and 59±3.4% compared to control; p<0.001). These results suggest that DEHP may induce reproductive disorders that can be inherited by subsequent generations. Histone 3 (H3) was significantly (p<0.05) upregulated in both plastic and DEHP treatments after 6 days of exposure, but not after 18 days of recovery. Hsp70-like expression showed to be unresponsive to either DEHP or microplastic exposure. Clearly, microplastics and plasticizers pose a serious threat to zooplankton and potentially to higher trophic levels.


Assuntos
Copépodes/efeitos dos fármacos , Dietilexilftalato/toxicidade , Plastificantes/toxicidade , Plásticos/toxicidade , Polietilenotereftalatos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Austrália , Copépodes/genética , Copépodes/crescimento & desenvolvimento , Copépodes/metabolismo , Dietilexilftalato/química , Relação Dose-Resposta a Droga , Feminino , Expressão Gênica/efeitos dos fármacos , Dose Letal Mediana , Masculino , Tamanho da Partícula , Plastificantes/química , Plásticos/química , Polietilenotereftalatos/química , Reprodução/efeitos dos fármacos , Testes de Toxicidade , Poluentes Químicos da Água/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-28431779

RESUMO

Propranolol is a noncardioselective ß-blocker. It is reported to have membrane-stabilizing properties, but it does not own intrinsic sympathomimetic activity. Propranolol hydrochloride is used to control hypertension, pheochromocytoma, myocardial infarction, cardiac arrhythmias, angina pectoris, and hypertrophic cardiomyopathy. It is also used to control symptoms of sympathetic overactivity in the management of hyperthyroidism, anxiety disorders, and tremor. Other indications cover the prophylaxis of migraine and of upper gastrointestinal bleeding in patients with portal hypertension. This study provides a detailed, comprehensive profile of propranolol, including formulas, elemental analysis, and the appearance of the drug. In addition, the synthesis of the drug is described. The chapter covers the physicochemical properties, including X-ray powder diffraction, pK, solubility, melting point, and procedures of analysis (spectroscopic, electrochemical, and chromatographic). In-depth pharmacology is also presented (pharmacological actions, therapeutic dosing, uses, Interactions, and adverse effects and precautions). More than 60 references are given as a proof of the abovementioned studies.


Assuntos
Antagonistas Adrenérgicos beta , Propranolol , Antagonistas Adrenérgicos beta/química , Antagonistas Adrenérgicos beta/farmacocinética , Antagonistas Adrenérgicos beta/farmacologia , Antagonistas Adrenérgicos beta/uso terapêutico , Estabilidade de Medicamentos , Humanos , Hipertensão/tratamento farmacológico , Estrutura Molecular , Propranolol/química , Propranolol/farmacocinética , Propranolol/farmacologia , Propranolol/uso terapêutico
6.
PLoS One ; 10(7): e0133269, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26186526

RESUMO

Calanoid copepods are an important food source for most fish larvae. Their role as a natural prey item means that it is important to develop culture technology for copepods to meet the requirements of larvae culture in aquaculture hatcheries. Copepods have been cultured successfully for some time; however, the implications of long-term cultivation or domestication on copepod life history traits have not yet been assessed. Therefore, the aim of this study was to determine if the domesticated and wild populations of Parvocalanus crassirostris are phenotypically or physiologically different. Wild-caught P. crassirostris were compared to a long-held domesticated strain (>2 years) for size of developmental stage, fecundity and lifespan of adult females, culture density, ingestion rates, faecal pellet production and fatty acid profiles. The domesticated strain was significantly different from the wild strain in size (eggs, nauplii, copepodites and adults were larger in the domesticated strain), egg production (112.3 ± 1.8 eggs female(-1) vs. 64.6 ± 3.3 eggs female(-1)) and adult female lifespan (8.8 ± 0.1 days vs., 7.5 ± 0.1 days). At 1, 3 and 5 adults mL(-1), the domesticated strain performed significantly better than the wild strain in egg production (4189.8 ± 61.2, 11224.0 ± 71.7 and 21860.6 ± 103.6 eggs vs. 1319.5 ± 54.3, 2374.5 ± 80.9 and 4933.8 ± 269.5 eggs, respectively) and mean daily mortality rate (5.6% across all densities vs. 22.9 ± 1.6, 29.8 ± 1.2 and 31.3 ± 1.3%, respectively). The domesticated strain had significantly higher ingestion rates than the wild stain (888.4 ± 9.9 ng C l(-1) and 775.3 ± 11.2 ng C l(-1), respectively), while faecal pellet production was not significantly different between strains. Fatty acid profiles indicated higher levels (as % of total fatty acid) of long-chain polyunsaturated fatty acids in the domesticated strain (36.2±0.4%) than the wild strain (16.1±0.1%). Overall, this study found that the reproductive capacity and tolerance to the culture environment of the calanoid P. crassirostris have improved significantly due to domestication.


Assuntos
Aquicultura/métodos , Copépodes/crescimento & desenvolvimento , Animais , Ácidos Graxos/análise , Fezes , Comportamento Alimentar , Feminino , Estágios do Ciclo de Vida , Longevidade/fisiologia , Mortalidade , Óvulo/fisiologia , Queensland
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